Stabilized petroleum products and stabilizing compositions



Patented Jan. 1 1952 .i 'UNITEb' assassi,

STABILIZED PETROIZEUM PRODUCTS" AND STABILIZING COMPOSITIONS Charles B. Biswell, Woodstown, N. J .,.,assignor to M E. I. du Pont de Nemours & Company, Wilmington, Del., a. corporation of Delaware No Drawing? 2 Application May 21, Serial No. 94,756" i 20 Claims; 0112524123 'This invention relates to petroleum products "L which have been stabilized against oxidation and to new compositions of matter which are particularly efiective for stabilizing greases.

Petroleum products, such as gasoline, fuel oils,

lubricating oils and greases tend to oxidize and deteriorate in the presence of oxygen during storage and use. It has become common practice to inhibitsuch oxidation and deterioration by adding to such petroleum products phenols, amines and aminophenols, commonly called antioxidants. While, the use oi such antioxidants has met with considerable success, the petroleum products are frequently brought into contact with copper or copper compounds, or become contaminatedwith copper compounds, which catalyze the oxidation and deterioration of the petroleum .productsand also of the antioxidants contained therein. It has, therefore, become necessary to also add to the petroleum products other materials which will overcome the catalytic efiect of copper and compounds containing it, such other materials being called metal deactivators or copper deactivators.

.Usually,, reases are prepared by incorporating a metal soap into a petroleum oil, particularly a soap which causes the oil to gel. The most important and common soaps employed for this purpose are soaps of lithium, sodium, potassium, calcium. barium and aluminum or mixtures of such soaps. Such greases, like the petroleum oils greatly reduces the lubrication properties of the greases. Furthermore, this deterioration and oxidation is also catalyzed by metallic surfaces and ingredients, and particularly by copper and copper-containing metals, such as brass. This 2 l uclarkson and Pedersen, in Patent 2,353,690, dis- .close that 1-.(orthmhydroxy-arylidene) -aminoguanidines, represented .by 1 salicylalaminoguanidinamay beemployed together with an antioxidant,.in1organic. substances normally sub- 'ject. to -oxidation and containing or in contact with copper and copper-containing metals. They .disclose .that .the. .l-iortho-hydroxy-arylidene) aminog'uanidines act to overcome the catalytic effect of the metals. Such l-(orthohydroxyarylidene) -aminoguanidines are relatively expensive and. it is desirable to produce equivalent orbetter. efiects bycheaper materials.

'.It.is.an.object.oi. this invention to provide petroleum products which have been stabilized against oxidation and. deterioration by incorporating therein compounds which are particularly efiective both as antioxidants and as copper deactivators- Another object is to provide greases having particularlyhigh resistance to deterioration by oxidation, improved mechanical stability and which will undergo substantially less discoloration-during storage and use. A further object is to stabilize petroleum products by means of compounds which are exceptionally effective and yet which are materially less expensive. A still further object is to provide. new compositions 'of'matter which are particularly effective as antioxidants for greases and which are cheaper and may be more readily incorporated in greases than prior antioxidantcompositions. Further objects are to provide new compositions of matter and to advance the art. Still other objects will appear hereinafter.

Theabove and other objects may be accomplished in accordance with my invention which comprisesincorporating in petroleum products effect of copper and copper-containing metals is erately efiective. The response is not always proportional to the concentration of the amine in the grease and it is not always possible to prepare a grease with a desired high stability to I oxidation merely by increasing the concentration of the amine in the grease. Such amines are particularly ineffective in the presence of copper and copper-containing metals. Furthermore, many of such amines tend to discolor badly and impart such undesirable color to the greases, particularly when employed in high concentrations.

about 0.0001% to about 2% by weight of an equimolecular carboxylic acid salt of a l-(ortho-hy- 'droxy-arylidene) -aminoguanidine in which the arylidene group is'of the benzeneseries and in whichsalt the carboxylic acid contains at least 2 carbon atoms and consists of carbon and hydrogen atoms and 1 to 2 carboxyl groups. A particular feature comprises incorporating in a grease, composed substantially wholly of a petroleum oil and a metal soap, about 0.1% to about 2% by weight of a secondary aromatic amine consisting oi carbon, hydrogen and l to 2 secondary amino'nitrogen atoms and in which each of the 2 valences of eachnitrogen atom is satisfied by an aromaticradical and about 1% to about 2 basedfon the amine, of such an equimolecular carboxylic acid salt of a l-(ortho-hydroxy-arylidene) amin0gua'n idine. My invention also comprises the anti-oxidant compositions composed of about 99% to about 75% of the secondary aromatic amine and about 1% to about 25% of the salt." H

' I havejfouncl that the salts of the l-(orthohydroxysarylidene)-aminoguanidines of the character above described are both antioxidants and copper deactivators. They very effectively stabilize petroleum products against oxidation and deterioration in the absence of metal catalysts, such as copper. Also, when the petroleum products are in contact with or contain copper or its catalytically active compounds, such salts are particularly effective to deactivate the copper. I have found further that the combination of secondary aromatic amines and such salts is particularly effective to stabilize greases against oxidation and deterioration during storage and use, both in the presence and in the absence of copper and copper-containing metals. The effect of the combination is greater than the merely cumulative or additive effect of the ingredients. While most of the salts have molecular weights of about 2 to 3 times the molecular weight of the 1- (ortho hydroxy arylidene) aminoguanidine, they are somewhat more efiective on the weight basis, and hence have a molecular effectiveness of 2 to 3 times the effectiveness of the free base. Furthermore, the salts cost approximately onethird the cost of the free base. Thus, by my invention, I am able to produce petroleum products of improved, stability at nearly one-third the cost. At the same time, the salts inhibit the discoloration of the amines, and hence the antioxidant compositions of amine and salt are more stable toward discoloration.

The petroleum products which are to be stabilized comprise straight-run and cracked gasolines, fuel oils, lubricating oils, and lubricating greases. Preferably, the greases are composed substantially wholly of a petroleum oil and, a metal soap, such as the soaps of lithium, sodium, potassium, calcium, barium and aluminum. The petroleum oil, employed in producing such greases, will usually be a lubricating oil of the character ordinarily employed in producing greases of this type.

The salts of 1-(ortho-hydroxy-arylidene)- aminoguanidines may be added to the petroleum productsv as the sole antioxidant or as the sole combined antioxidant and copper deactivator. This has the advantage of obviating the necessity of adding two different agents to the petroleum productsan antioxidant and a copper deactivator. When the petroleum product contains or is in contact with copper or its catalytically active compounds or it is contemplated that it will become contaminated or be brought into contact with copper or its catalytically active compounds, larger amounts of salt will be employed; an amount sufficient to deactivate the copper and an additional amount to thereafter exert the desired antioxidant efiect. In some cases, particularly in cracked gasoline. and in greases, it will be desired to employ the salt primarily for its copper deactivating, effect and to add another antioxidant for the major anti.- oxidant effect. 7 In such latter event, any, of the usual antioxidants, known to be effective for the particular petroleum product, may be employed with my salts.

The aromatic amines, which may be employed as antioxidants in greases with the salts, are those ordinarily employed for the stabilization of such greases. Particularly, such aromatic amines are secondary aromatic amines consisting at carbon, hydrogen and 1 to 2 secondary amino nitrogen atoms and in which each of the. 2 valences of each nitrogen atom is satisfied by an aromatic. radical, that is, the nitrogen. is directly bonded to a carbon atom which is a member of 4 an aromatic ring. Preferably, each aromatic radical contains 1 to 2 benzene rings, that is, is selected from the benzene, naphthalene and biphenyl series. Aromatic amines, which I have found to be particularly desirable in the antioxidant compositions of my invention, are

Diphenylamine Phenyl-a-naphthylamine Phenyl-p-naphthylamine Di-a-naphthylamine Di-p-naphthylamine N,N"-diphenyl benzidine N ,Nedi-,B-naphthyl-p-phenylenediamine N ,N -diphenyl-p -phenylenediamine Still other secondary aromatic amines, which may be employed in such compositions. are- Ditolylamines Phenyl-tolylamines Tolyl-naphthylamines N,N-ditolyl benzidines N,N-ditolyl-p-phenylenediamines N ,N' -diphenyl-toluylenediamines N ,N -dipheny1-naphthylenediamines ll,l ,l -ditolyl-naphthylenediamines The salts, which are to be employed in accordance with my invention, are the equimolecular carboxylic salts of the l-(ortho-hydroxy-arylidene) -aminoguanidines, that is, the salts formed from equimolecular proportions of thecarboxylic acids and the 1-(ortho-hydroxy-arylidene)- aminoguanidines. The l-(ortho-hydroxy-arylidene)-aminoguanidines, which are employed to produce the salts, are those in which the arylidene group is of the benzene series. The term arylidene is employed in its ordinary restricted sense to mean a divalent aromatic radical consisting of carbon and hydrogen. Representative 1-(ortho-hydroxy-arylidene) aminoguanidines are l-(salicylalaminoguanidine, 1-(2-hydroxy-5-methylbenzal)-aminoguanidine and 1- (2'-hydroxy-5- ter. butylbenzal) aminoguanidine. Of. these, l-salicylalaminoguanidine is preferred.

The 1- (ortho-hydroxy-arylidene) -aminoguanidines may be made by the method disclosed by Wedekind in Ben, 31, 2353 (1898). According'to such process, aminoguanidine nitrate is reacted with the ortho-hydroxy-aromatic aldehyde in warm water. Treatment of the resulting mixture with potash. solution precipitates the free base.

Theacids, which maybe employed to produce the salts of'my invention, are those. carboxylic acids which contain at leastv 2 carbon-atoms and consist of carbon and hydrogen atoms and 1 to 2 carboxyl groups; Preferably, the acids are-of the aliphatic series and contain from 6 to. 40 carbon atomsand, particularly, those which contain a single. carboxyl group. Representative acids, which may beemployed to produce satisfactory salts. useful in my invention, are

Oleic acid Acetic acid Naphthenic" acids Linoleic acid Caproic acids C'apric acid Caprylicacid Myristic acid Laurie acid Arachidic acid Palmitic acid Behenic acid Stearic acid Cerotic acid Phenylstearic acid Melissic acid Linoleic acid dimer Decylenic acid Sebacic acid Undecylenic acid Benzoic acid Erucic acid l-salicylalaminoguanidine monoacetate (M. P. 0;) l-salicylaminoguanidine monobenzoate P. 170 C.) and l-salicylaminoguanidme monosebacate (M. P. 193 C.) are high melting materials and are only slightly soluble in hydrocarbons, so that it is difiicult to properly incorporate them into the petroleum products, and hence such salts are not preferred. On the other hand, the salts of the monocarboxylic aliphatic acids and of linoleic acid dimer melt in the range of about 50 C. to about 98 C. and are fairly soluble in hydrocarbon oils so that they can be readily incorporated into the petroleum products, usually, by heating them above their melting points with the oil or grease or a portion thereof. The term aliphatic is employed in its broad sense to include acids containing alicyclic rings as well as the acyclic acids. The preferred salts are the l-salicylalaminoguanidine monoleate, l-salicylalaminoguanidine mononaphthenates, and l-salicylalaminoguanidine mono-linoleic acid dimer. The naphthenic acids are usually obtained from crude petroleum or its distillates as mixtures of homologous aliphatic acids containing from 7 to about 20 carbon atoms and a cyclopentane ring carrying alkyl side chains with the carboxyl groups in the side chain and usually on the end of the side chain. The naphthenic acid salts, employed in the examples, were prepared from a mixture of naphthenic acids having an average molecular weight of 242, which corresponds to an average of approximately 15 carbon atoms in each acid molecule. The linoleic acid dimer is a carboxylic acid of the following formula- The salts of the 1-(ortho-hydroxy-arylidene) aminoguanidines are advantageously prepared in substantially quantitative yields by mixing substantially equimolecular proportions of the carboxylic acid, an ortho-hydroxy aromatic aldehyde and an inorganic acid salt of the aminoguanidine in an organic solvent with mild heating and then adding water to precipitate the product, which is then filtered and dried. The inorganic acid salts of aminoguanidine, which may be employed in such reaction, are the bicarbonate, the nitrate, the hydrochloride and the phosphate. Since the bicarbonate is a readily available commercial product, it will ordinarily be used. The solvents, which may be used, include aliphatic alcohols of l to 4 carbon atoms, such as methyl, ethyl, isopropyl and tertiary butyl alcohols, and liquid aromatic hydrocarbons, such as benzene, toluene and the xylenols. For example, a mixture of 408 grams of aminoguanidine bicarbonate, 373 grams of salicylaldehyde, 840 grams of oleic acid and 300 cc. of methyl alcohol was agitated at 65 C. to 70 C. for 3 hours in a 3 liter glass flask, the reaction mass was added to 3600 cc. of water with stirring, the resulting solid product filtered,

washed withwater and air dried, yielding 1426 grams of l-salicylalaminoguanidine monoleate having a melting range of 60 C, to C. This method was followed in preparing the other salts disclosed herein. The methods of preparing the salts are disclosed in more detail in my copending application, Serial No. 94,755, filed May 21, 1949, which claims the preferred salts.

When greases are to be stabilized by a combination of a secondary aromatic amine and a salt, the amount of the amine incorporated in the grease may be from about 0.1% to about 2% by weight, but will usually and preferably be from about 0.25% to about 1%. The salt of the l-(ortho-hydroxy arylidene) aminoguanidine may be employed in the proportion of from about 1% to about 25% by weight, based on the secondary aromatic amine, and preferably from about 5% to about 10%.

The secondary aromatic amine and the salt of the 1 (ortho-hydroxy-arylidene) -aminoguanidine may be separately added to the grease. However, it will generally be preferred to mix them so as to provide an antioxidant composition composed of the two ingredients in the desired proportion. Such compositions may be made by melting the amine and the salt together, whether the salt appears to dissolve in the amine. The amine and the salt, or the mixtures thereof, will usually be dissolved or dispersed in part of the oil to be employed in man ufacturing the grease, but they may be incorporated in the preformed grease by milling or by stirring While heating tomelt the inhibitors.

In order to more clearly illustrate my inven tion, preferred modes of carrying the same into efiect and advantageous results to be obtained thereby, the following examples are given:

EXAMPLE I For the purpose of illustrating the metal deactivating characteristics of these compounds, I have chosen to show the property of salicylalaminoguanidine oleate of suppressing the catalytic activity of copper in gasoline. The samples of gasoline, used in the following tests, were completely refined thermal cracked naphtha untreated with chemical agents such as dyes, antioxidants and anti-knocks. The compounds of the present invention were tested in accordance with A. S. T. M. method D522-46 for the gum stability of gasoline. The results of this test are expressed in terms of induction period (in minutes), the period required for oxygen absorption to begin. N-normal butyl-p-aminophenol, abbreviated BAP, has been chosen as a representative gasoline antioxidant. It was added in small quantity to gasoline containing no copper, to the same gasoline containing one part per million of dissolved copper added as the oleate, and to gasoline containing both the dissolved copper and salicylalaminoguanidine oleate.

The experimental results are given in the following Table I:

- Table I Concentration I d ti n uc on Deactivator $3 633 Period,

BAP, Wt. Copper, Minutes Per Cent P. P. M.

(l. 0 O. O

0. 002 1.0 Salicylalaminoguanidine oleate-.. 391

7 It will be observed that the catalytic effect of copper is counteracted by this compound.

EXAIl/IPIzE II To illustrate the utility of the compounds of this invention as antioxidants for gasoline, they were evaluated in cracked gasoline which had been thoroughly refined to remove metals. The antioxidant characteristics were compared with 2,6-ditertiarybutyl--methylphenol which is a well established commercial gasoline antioxidant.

The various products shown below were added at 0.005% by weight to the gasoline and the induction periods were then determined by the method described in Example I... The weight efiectiveness of 2,6-ditertia-ry-4-methylphenol, which at 0.005 wt. per cent increased the induction period from 185 to 243 minutes, was arbitrarily assigned the molar eiilciency of 100.

The experimental results are given in thefollowing Table II:

Table II lar test used is commonly referred to as the Accelerated Norma-Hofiman Stability Test and is described in the proceedings of the American Society for Testing Materials, volume 38, part II, 1938, in an article entitled, Some applications of an accelerated testfor determining the chemical stability of lubricating greases. In this test a weighed sample of the grease to be tested is charged into a glass container, with or Without brass catalyst, and the container is placed in a suitable bomb and subjected to a pressure of 110 pounds of oxygen at 210? to 212 F. for a certain number of hours or until the pressure has dropped a certain number of pounds. v I

In these experiments, all of the samples were run in the presence of brass. Included the products tested were samples treated with phenyl: a-naphthylamine, which is a conventional grease stabilizer having wide commercial application,

Induction Per Cent Efficiency Antioxidant Period,

Minutes Wt. Basis Molar Basis None 2,6-ditertiarybuty1-4-methylpheno1le l-salicylalaminoguanidine monolauratm I-Salicylalaminoguanidine monocaproate 1-Sa 1icylalami.noguanldine monolinolemc a mer 1-Salicylalamineguanidine monoleatenh, .i

It will be observed that the compounds of this invention are efiective gasoline antioxidants and and with salicylalaminoguanidine base, respec tively. The results are shown in Table III:

Table III Norma-Hoilman Stability Test-Hours to lbs] sq. in. pressure drop Stabilizers None (unstabilized) 5% l-salicylalaminoguanidine monopalmitatm,

that their molar effectiveness is much higher than the salicylalaminoguanidine base.

EXAMPLE III As another example of the usefulness of the compounds of this invention, samples of a commercial unstabilized calcium soap grease were treated with 0.5% by weight of several different organic acid salts of salicylalaminoguanidinef EXAMPLE .1v

Samples of a commercial unstabilized calcium soap grease were treated with 0.45% by weight of various secondary aromatic amides together with 0.05% of l-salicylalaminoguanidine monoleate (A), making 0.5% by weight of total stabilizers based on the grease. Samples of the same grease were treated with 0.5% by weight of the amines alone and still another sample was treated with 0.5% of l-salicylalaminoguanidine monoleate (A) alone.

The stabilizers were incorporated into the commercial samples and the samples were tested in the same way as in Example III.

In this particular set of experiments, the greases were all run in the presence of brass disks to 25 pounds pressure drop. The results of the tests are as follows:

Table IV.

Stabilizers added to the grease Hours to 25 Pounds Pressure Drop 0.5% phenyLa-naphthy mP Nne t 0.5% l-salicylalaminoguanidine.monoleate (A) phenyl-B-naphthylamme 0.45% phenyl-B-naphthylamine 0.05% (A) di- -naphthylamim 0.45% phenyl-a-naphthylamine 0.05% (if.

poppopoooo diphenylam ,N"-diphenyl-p-phenylenediamine 0.05% (A) --I diphenylamiue 0.05% (A) It will be noted that, in every case, the effect of the combination of stabilizers is materially greater than the mere cumulative eiTect of the ofthe same greases were subjected to the Norma- Hoffman accelerated oxidation stability test as described in Example III. These tests were made components of the combination in the absence of added metal catalysts. The results of the tests are as follows:

' LE v T bl VI a e v Samples of a commercial, unstabilizedcalcium soap grease were treated with 0.45% diphenylamine together with 0.05% by weight, based on 053233533 235335 Eg s the grease (10 by weight based on the d1phenyl- 0f stablhzer p amine), of various equimolecular carboxylic acid salts of l-salicylalaminoguanidme. A sample of Lithium S03 a 8 g gg the same grease was treated with 0.5% by weight p Se j 25 6 360 of diphenylamine and still other samples were calciumsoap grease g Z8 treated with 0.5% by weight of some of the salts S d 25 260 of l-salicylalaminoguanidine alone. The arious 0 mm .m g 3 stabilizers were homogeneously mixed with the Sodiummalcmmsoap 1 25 360 grease as described in Example III. 1.0 24 v 300 The grease samples were subjected to the Norma-Hoffman accelerated oxidation stability VII test as described in Example III. In this set of EX LE experiments ,the grease samples were all runv in Samples of a commercial, unstabilized calcium the presence of brass disks to 25 poundspressure soap gr were treated w y wei drop. The results of the test are as follows: of dip y amine, with 0.5% by wei ht f- Table V No. Stabilizers added gg gfig gggg None 14 0.5% diphenylamine 106 0.45%? (tliphenylamine 0.05% l-salicylalaminoguanidine mono- 130 506* 8 P 0.45% diphenylamine 0.05% l-salicylalaminoguanidine monocaprylate 142 0.45% diphenylamine 0.05% l-salieylalaminoguanidine mono- 1 caproate 132 0.5% l-salicylalaminoguanidine monolaurate. 23 0.45% diphenylamine 005% l-salicylalam laurate 142 0.5% l-salicylalaminoguanidine monop 53 0.45% diphenylamine 0.05% l-salicylalaminoguanidine monophenylstearate 130 0.45% diphenylamine a l-salicylalaminoguanidine monolinoleic acid dimer 142 0.45% diphenylamine 0.05% l-salicylalaminoguanidine monobenzoate 118 0.45% diphenylamine 0.05% l-salicylalaminoguanidlne monosebacate 0.5% l-salicylalaminoguanidine mononaphthenates 64 0.45% diphenylamine 0.05% l-salicylalaminoguanidino mononaphthenates 146 16-; 0.45%diphenylamine 0.05% l-salleylalaminoguanidine monopalmitate 126 16 0.45% diphenylamlne 0.05% l-salicylalaminoguanidine monostearate 130 EXAMPLE VI l-salicylalaminoguanidine monoleate and with Unstabilized commercial greases of several difierent metal soaps were treated. with varying amounts Of-a stabilizer composition consisting.

of a mixture.;of 90% diphenylamine and 10% l-salicylalaminoguanidine monoleate: The stabilizer composition was added to the grease sample as described in Example III.

.The treated grease samples and control samples 75 oxidation, method which is described in.Examp1e 1 0.5% by weight of mixtures of diphenylamine with 1%, 5%, 10%, 15%, 20% and 25% of l-salicylalaminoguanidine monoleate.

The samples were prepared for testing by thoroughly mixing the stabilizers with the grease as described in Example III. The grease samples were tested by the Norma-Hoffman accelerated aeeweei III. In this set of experiments, the grease samples were all run in the presence of brass disks, which served as a catalyst, to'25 pounds pressure drop. The effect of various proportionate amounts of 1-salicylalaminoguanidine monoleate (abbreviated to SAG-monoleate) together with diphenylamine (abbreviated 'to'DPA') are given in the following Table VII:

Table VI] Stabilizers added Hours to 25 Pounds Pressure Drop 0.5% mixture of 99% DPA and 1% SAG-monolea 0.5% SA G-monoleate 0.5% mixture of 95% DPA and 5% SAG-monoleate. 0.5% mixture of 90% DPA and SAG-monoleate.. 0.5% mixture of 85% DPA and SA G-monolcate-. 0.5% mixture of 80% DPA and 'SAG-monoleate 0.5% mirtureof 75% EPA and SAGHnbnoleata.

None (unstabilized) e I Q DPA This exampleparticularly illustrates that the combination of stabilizers unexpectedly produces results considerably superior to the mere additive effects of the individual components. Since diphenylamine gave a value of 106 and the 1- salicylalaminoguanidine monoleate gave a value or 100, it would be expected that the values of Nos. 3 to 8 would be between 106 and 100, such values decreasing as increasing amounts of the diphenylamine were replaced by l-salicylalaminoguanidine monoleate.

EXAMPLE VIII will be readily apparent to those skilled in the art that many variations and modifications can be made within the limits hereinbefore set "forth without departing from the spirit or scope of my. invention. 7

It will be apparent that, by my invention, I am able to produce petroleum products of substantially improved stability toward deterioration and oxidation and at a substantial reduction in cost. The preferred salts of the l-(ortho-hw droxy-arylidene) -aminoguanidines of my invention have lower melting points than the tree base and are more soluble in hydrocarbons so that they may be more readily incorporated in petroleum products and, particularly, in mils and greases. It is also apparent that I am able to provide new, more stable, more eiiective and less ex ensive antioxidant compositions which may be readily and easily incorporated in oils and greases. Therefore, it will be apparent that my invention, constitutes a valuable advance and contribution to the art.

I claim:

1. A petroleum product having incorporated therein about 0.0001% to about 2% of an equi- Table VIII No Catalyst Brass No. Grease Composition Pounds Pounds Hrs. Pressure Hrs. Pressure rop Drop Grease (calcium soap) (A) 25 14 :25 (AH-0.5% diphenylamine 430 25 139 25 (AH-A57, diphenylamine+. G (has 500 21 162 25 (A)+.45% diphenylamine+.05% SAG-oleate. 500 20 170 25 Grease (sodium soap) (B) 33 25 12 25 (EH-0.5% diphenylamine 33G 25 112 25 (B)+.45% diphenylamine+.05% SAG (base) I 406 25 122 25 (B)+.45% diphcnylamine+.05% SAG-cleate 486 25 130 25 From the above results, it will be seenthat the l-salicylalaminoguanidine monoleate (the molecular carboxylic acid salt of. a 1- (ortho-hyq salt) is somewhat more'eifective than the i-salicylaminoguanidine (the base) on the weight droxyarylidene) -aminoguanid in'e" in which the arylidene group is of the benzene series and in' which salt the carboxylic acid contains at least 2 carbon atoms and consists of carbon and hydrogen atoms and 1 to 2 carboxyl groups.

. 2. A petroleum'product having incorporated therein about 0.000l% to about 2% of an equimolecular carboxylicacidsalt of a l-(ortho-hy- K droxy-arylidene) -aminoguanidine in which the arylidene group is of the benzene series" and-inv which salt the carboxylic acid is of the aliphatic series, contains 6 to 40 carbon atoms and consists of carbon and hydrogen atoms andlto 2 carboxyl groups; said salt having a melting point in the range of about 50 C. to about 98 C.

" 3. A petroleum product having incorporated therein about 0.0001% to about 2% of an equimolecular carboxylic acid salt of a l-(ortho-hydroxy-arylidene)-aminoguanidine in which the arylidene group is of the benzene series and in which salt the carboxylic acid is of the aliphatic series, contains 6 to 40 carbon atoms and consists of carbon and hydrogen atoms and 1 carboxyl group; said salt having a melting point in the range of about 50 C. to about 98 C.

4. A petroleum product having incorporated therein about 0.0001% to about 2% of a l-(orthohydroxy-arylidene)-aminoguanidine monoleate in which the arylidene group is of the benzene series. '5. A petroleum product having incorporated therein about 0.0001% to about 2% of a l-(orthohydroxy-arylidene) -aminoguanidine mononaphthenate in which the arylidene group is oi the benzene series. Z

6. A grease, composed substantially wholly of a petroleum oil and a metal soap, having incorporated therein about 0.001% to about 2% of an equimolecular carboxylic acid salt of a l-(orthohydroxy-arylidene) -aminoguanidine in which the arylidene group is of the benzene series and in which salt the carboxylic acid contains at least 2 carbon atoms and consists of carbon and hydrogen atoms and 1 to 2 carboxyl groups.

'7. A grease, composed substantially wholl of a petroleum oil and a metal soap, having incorporated therein about 0.001% to about 2% of an equimolecular carboxylic acid salt of a 1-(orthohydroxy-arylidene) -aminoguanidine in which the arylidene group is of the benzene series and in which salt the carboxylic acid is of the aliphatic series, contains 6 to 40 carbon atoms and consists of carbon and hydrogen atoms and 1 to 2 carboxyl groups; said salt having a melting point in the range of about 50 C. to about 98 C.

8. A grease, composed substantially wholly of a petroleum oil and a metal soap, having incorporated therein about 0.001% to about 2% of an equimolecular carboxylic acid salt of a l-(orthohydroxy-arylidene) -aminoguanidine in which the arylidene group is of the benzene series and in which salt the carboxylic acid is of the aliphatic series, contains 6 to 40 carbon atoms and consists of carbon and hydrogen atoms and 1 carboxyl group; said salt having a melting point in the range of about 50 C to about 98 C.

9. A grease, composed substantially wholly of a petroleum oil and a metal soap, having incorporated therein about 0.1% to about 2% of a secondary aromatic amine consisting of carbon, hydrogen and 1 to 2 secondary amino nitrogen atoms and in which each of the two valences of each nitrogen atom is satisfied by an aromatic radical containing 1 to 2 benzene rings; and about 1% to about 25%, based on the amine, of an equimolecular carboxylic acid salt of a 1-(ortho-hydroxy-arylidene) -aminoguanidine in which the arylidene group is of the benzene series and in which salt the carboxylic acid contains at least 2 carbon atoms and consists of carbon and hydrogen atoms and 1 to 2 carboxyl groups.

10. A grease, composed substantially wholly of a petroleum oil and a metal soap, having incorporated therein about 0.1% to about 2% of a secondary aromatic amine consisting of carbon, hy-

drogen and 1 to .2 secondary amino nitrogen atoms and in which each of the two valences of each nitrogen atom is satisfied by an aromatic radical containing 1"to 2 benzene rings: and about 1% to about 25%, based on the amine, of an equimolecular carboxylic acid salt of l-salicylalaminoguanidine in which the carboxylic acid contains at least 2 carbon atoms andconsists of carbon and hydrogen atoms and 1 to 2 carboxyl groups.- t

11. A grease, composed substantially wholly of a petroleum oil and a metal soap, having incorporated therein about 0.1% to about 2% of a secondary aromatic amine consisting of carbon, hydrogen and 1 to 2 secondary amino nitrogen atoms and in which each of the two valences of each nitrogen atom is satisfied by an aromatic radical contining 1 to 2 benzene rings; and about 1% to about 25%, based on the amine, of an equimolecular carboxylic acid salt of 'l-salicylalaminoguanidine in which the carboxylic acid is of the ali-- phatic series, containsfi to 40 carbon atoms and consists of carbon and hydrogen atoms and 1 to 2 carboxyl groups; said salt having a melting point in the range of about 50C. to about 98 C.

12. Gasoline having incorporated therein about 0.0001% to about 0.01% of an equimolecular carboxylic acid salt of a l-(ortho-hydroxy-arylidene) -aminoguanidine in which the arylidene group is of the benzene series and in which salt the carboxylic acid contains at least 2 carbon atoms and consists of carbon and hydrogen atoms and 1 to 2 carboxyl groups.

13. Gasoline having incorporated therein about 0.0001% to about 0.01% of an equimolecular carboxylic acid salt of a l-(ortho-hydroxy-arylidene) -aminoguanidine in which the arylidene group is of the benzene series and in which salt the carboxylic acid is of the aliphatic series, contains 6 to 40 carbon atoms and consists of carbon and hydrogen atoms and 1 to 2 carboxyl groups; said salt having a melting point in the range of about 50 C. to about 98 C.

14. A composition composed of about 99% to about 75% of a secondary aromatic amine consisting of carbon, hydrogen and 1 to 2 secondary amino nitrogen atoms and in which each of the two valences of each nitrogen atom is satisfied by an aromatic radical; and about 1% to about 25% of an equimolecular carboxylic acid salt of a 1- (ortho-hydroXy-arylidene) -aminoguanidin'e in which the arylidene group is of the benzene series and in which salt the carboxylic acid contains at least 2 carbon atoms and consists of carbon and hydrogen atoms and 1 to 2 carboxyl groups.

15. A composition composed of about 99% to about 75% of a secondary aromatic amine consisting of carbon, hydrogen and 1 to 2 secondary amino nitrogen atoms and in which each of the two valences of each nitrogen atom is satisfied by an aromatic radical; and about 1% to about 25% of an equimolecular carboxylic acid salt of a 1-(ortho-hydroxy-arylidene)-aminoguanidine in which the arylidene group is of the benzene series and in which salt the carboxylic acid is of the aliphatic series, contains 6 to 40 carbon atoms and consists of carbon and hydrogen atoms and 1 carboxyl group; said salt having a melting point in the range of about 50 C. to about 98 C.

16. A composition composed of about 99% to about 75% of a secondary aromatic amine consisting of carbon, hydrogen and 1 to 2 secondary amino nitrogen atomsand in which each of. the two valences of each nitrogen atom is satisfied by an aromatic radical containing 1 to 2 benzene rings; and about 1% to about 25% of an equimolecular carboxylic acid salt of l-salicyl- 15 alaminoguanidine in which the 'carboxylicacid contains at least 2 caz'bon'atoms and consists or carbon and hydrogen atoms and l to 2 carboxyl groups.

17. A composition composed of about 99% to about 75% of 'a secondary aromatic amine consisting of carbon, hydrogen and 1 to 2 secondary amino nitrogen atoms and in which each of the two valences of each nitrogen. atom is satisfied by an aromatic radical containing 1 to 2 benzene rings; and about 1% to about 25% of an co ui molecular carboxylic acid salt of l-salicylalaminoguanidine in which the carboxylic acid is of the aliphatic series, contains 6 to 40 carbon atoms and consists ofcarbon and hydrogen atoms and-1 to 2 carboxyl groups; said salt having a meltingpoint in the range of about 50 G. to about 98 C1 I 18. A composition composed of about 99% to about 25% of a secondary aromatic amine consisting of carbon, hydrogen and 1 to 2 secondary amino nitrogen atoms and in which each of the two valences of each nitrogen atom is satisfied by anaromatic radical containing 1 to 2 benzene rings; and about 1% to about 25% of an equimolecular carboxylic acid salt of l-salicyl alaminoguanidine in which the carboxylic acidis of the aliphatic series, contains 6 to 40 carbon atoms and cnsists of carbon and hydrogen atoms and 1 carboxyl group; said salt having a melting point in the range of about 50" C. to about 98 C. I

19. A composition composed of about 99% to about 75% of a secondary aromatic amine consisting-of carbon, hydrogen and 1 to 2 secondary amino nitrogen atoms and in which each of the two valences of each nitrogen atom is satisfied by an aromatic radical containing 1 to 2 benzene rings; and about 1% to about of l-salicylalaminoguanidine monoleate. I

20. A composition composed of about 99% to about of a secondary aromatic amine consisting of carbon, hydrogen and 1 to 2 secondary amino nitrogen atoms and in which each of the two valences of each nitrogen atom is satisfied by an aromatic radicaicontaining 1 to 2 benzene rings; and about 1% to about 25% of l-salicylalaminoguanidine mononaphthenate, v V 4 I CHARLES E. BISWELL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date ,7 2,221,207 Sibley Nov. 12, i940 2,243,485 Musselman' May 27, 1941 2,275,264 Musselman et a1. Mar. 3, 1942 2,282,513 Downing et a1. May 12,1942 2,323,948 Von Bramer July 13, 1943 2,353,690 Cla'rkson et al. 1 July 18; 1944 2,361,339 White et a1. Oct. 24;, 1944 2,469,745 Robertson May 19, 1949 2,480,449 Cocroft et a1. Aug. 30, 1949 2,503,969 Rudl et a1. Apr. 11-, 1950 2,515,133 Morway July 11, 1950 

1. A PETROLEUM PRODUCT HAVING INCORPORATED THEREIN ABOUT 0.0001% TO ABOUT 2% OF AN EQUIMOLECULAR CARBOXYLIC ACID SALT OF A 1-(ORTHO-HYDROXY-ARYLIDENE)-AMINOGUANIDINE IN WHICH THE ARYLIDENE GROUP IS OF THE BENZENE SERIES AND IN WHICH SALT THE CARBOXYLIC ACID CONTAINS AT LEAST 2 CARBON ATOMS AND CONSISTS OF CARBON AND HYDROGEN ATOMS AND 1 TO 2 CARBOXYL GROUPS. 